Tape line

Drag each tick to where your tape started and ended.

The black line is fixed in the middle of the frame. Move the slab instead: drag to pan, wheel or pinch to zoom, and use the rotate handle or arrow keys to tilt until the slab's long axis lies on the line.

Tilt the slab { transform.tiltDeg = Number(event.currentTarget.value); redraw(); syncCalibration(); }} /> {((transform.tiltDeg % 360) + 360) % 360}°

Zoom the slab { changeZoom(Number(event.currentTarget.value) / (transform.zoom * 100)); }} /> {Math.round(transform.zoom * 100)}%

Crop fill % {cropFill}%

Arrow keys tilt the slab; Shift + arrow adjusts by 0.1°. The last tick you grabbed takes the up/down keys (1px, or 0.1px with Shift). Use +/− to zoom; double-click the slab to fit.